A Case Study in Conservation Arboriculture.
This post highlights a greater need for eduction in terms of care of large trees. We use the term “conservation” to convey the thought of preserving valuable resources. In this case, the resource is a large cottonwood tree. The Poplar genus is often regarded as a weed tree in the world of urban forestry. However, before leaping to a conclusion that is full of subjective bias, it is important to understand the unique ecological impact that this species provides. The tree here is located along a water ditch trail in a municipality that is, to a great degree, located within a river’s flood plain. It is the only large tree for quite some distance and may provide a greater benefit in water management than all of the other small trees growing within the immediate vicinity combined. It also has a fairly significant risk to the public due to a species habit of shedding large branches more often than some other trees. So the question that should be asked is how to manage the risks while preserving the benefits this tree provides. This usually requires pruning of the tree; for a cottonwood this might even mean reduction of fairly substantial parts.
Long story short, the initial pruning of the tree was performed in 2008. A follow-up should have been done last year; further reductions on five year cycles seek to eventually bring the tree’s overall geometry to be a much smaller and more manageable size. However, rather than prune the tree, the city put out a call for removal and last week the tree was made risk free, unless of course you count the risk to nearby residents in potential increase in water flow and/or flooding which actually increases now that the tree is gone.
Remember – no risks from trees also means no benefits from trees.